Intra and Extra-granular Disintegrant Properties of Modified Underutilised Red Lima Bean Starch in Paracetamol Tablet Formulation

Abstract Red lima bean (Phaseolus lunatus Linn) Family Fabaceae, has been modified by succinylation and annealing, and used as intra- and extra-granular disintegrants at concentrations of 5 and 10 %w/w in paracetamol tablet formulation in comparison with corn starch BP. The starches were characterised using FT-IR spectroscopy, SEM, proximate analysis, physicochemical and functional properties. FT-IR spectrometry revealed characteristic peaks at 1575.53 and 1713.99 cm-1 for the succinylated starch while the annealed showed no significant difference from the native starch. Modifications did not alter the ovoid shape of the native starch but reduced the particle size. Succinylation improved water absorption capacity, solubility and swelling of lima bean starch but annealing reduced the parameters. Tablets with disintegrants of lima bean starches generally had higher crushing strengths and lower friability than tablets with corn starch. Modifications reduced the disintegration time of the tablets when the starches were incorporated intra-granularly, which suggested particle-particle bond interruption and destruction of hydrogen bonds as mechanism of disintegration. Tablets containing 10 %w/w succinylated red lima bean starch incorporated intra-granularly had the highest disintegration efficiency ratio, DER, indicating a great balance between mechanical and disintegration properties. Modified red lima bean starches incorporated intra-granularly into paracetamol tablets led to faster disintegration and could efficiently substitute corn starch as disintegrant.

Microencapsulación de aceite esencial de tomillo (Thymus vulgaris) en matrices poliméricas de almidón de ñame (Dioscorea rotundata) modificado / Microencapsulation of thyme (Thymus vulgaris) essential oil in polymeric matrices based on modified yam (Dioscorea rotundata) starch

Los aceites esenciales son conocidos por sus numerosas actividades biológicas y organolépticas, pero su empleo suele verse limitado por su alta volatilidad y tendencia a degradarse. La microencapsulación es una estrategia válida para superar estos inconvenientes. En este trabajo se empleó almidón de ñame (D. rotundata), el cual fue sometido a procesos de hidrólisis y lipofilización, empleando anhídrido dodecenilsuccínico (DDSA); esto incrementó significativamente las capacidades captadora de aceite y emulsificante (tensoactiva) del almidón nativo, el cual se empleó para microencapsular aceite esencial de tomillo, que en estudios previos demostró potente actividad antibacteriana sobre las cepas involucradas en el desarrollo del acné. La microencapsulación se llevó a cabo por microparticulación lipídica sólida, seguida de emulsificación. Esta alcanzó una eficiencia superior al 98%, y el producto obtenido, desafiado en diversas pruebas, demostró capacidad de retener más del 90% del aceite esencial en condiciones de evaporación, evitando su oxidación y el cambio en su perfil de composición. Finalmente, las microcápsulas de aceites esenciales de tomillo, al ponerse en contacto con las bacterias del acné, mantuvieron su actividad bactericida. Los resultados de este trabajo aportan al desarrollo de formulaciones farmacéuticas, cosméticas y alimentarias estables y funcionales de aceites esenciales, al protegerlos de la evaporación y degradación.

Essential oils are known for their numerous biological and organoleptic activities, but their use is often limited by high volatility and tendency to degrade. Microencapsulation is a valid strategy to overcome these drawbacks. In this paper starch yam (D. rotundata) was used, which was subjected to hydrolysis processes and lipophilization using dodecenyl succinic (DDSA) anhydride, this significantly increased the scavenging capacity of oil and emulsifier (surfactant) of native starch, which was used to microencapsulate thyme essential oil, that in previous studies showed potent antibacterial activity on strains involved in the development of acne. Microencapsulation was conducted by microparticulation solid lipid, followed by emulsification. This reached an efficiency of over 98%, and the product obtained, challenged by various trials, demonstrated ability to hold more than 90% of essential oil under evaporation conditions, avoiding oxidation and change in composition profile. Finally, the microcapsules of essential oil of thyme at contact the acne bacteria, maintained its bactericidal activity. The results of this study contribute to the development of pharmaceutical, cosmetic and food formulations stable and functional based on essential oils, to protect degradation and evaporation.